Grinding apparatus.



H. H. HITCHCOCK. GRINDING APPARATUS.

'APPLICATION IILED JULY 19, 1907. RENEWED JULY 12, 1909.

Patented Sept. 21, 1909. a sHHHTsfsHHHT 1.

INVENTO R llll lllnllllll. ||||I|||||l m l 1\-2 d S H M a a@ j,

H. K. HITCHCOCK. GRINDING APPARATUS.

APPLICATION FILED JULY 19, 1907. BBNEWED JULY 12, 1909.

Patented Sept. 21, 1909.

3 SHEETS-SHEET 2.V

' H. K.- HITGHGOGK.

, GRINDING APPARATUS.

APPLICATION FILED JULY 19, 1907. RENEWED JULY 12, 1909.

934,612. Patented sept.21,1909.

3 SHEETS-SHEET 3.

' WBTNESSES sfrnrns rarnn'r orari/*ia HALBERT K. HITCHCOCK, F TARENTUM, PENNSYLVANIA.

GRINDING APPARATUS.

Application tiled July 19, 1907, Seria1 No. 384,640. Renewed July 12, 1909.

- and State of Pennsylvania, have invented certain new and useful Improvements in Grinding Apparatus, of which the following is a specification.

My invention relates to grinding appa-ratus and particularly to the apparatus for grading and supplying the abrading matell '11 v l. ll l r rml used 1n glass grinding oper ations. lhe

invention has for its principal objects: to provide an arrangement of apparatus wherein an accurate grading of the abrading material is secured and one wherein those portions of the material inefficient for abrasives or more valuable for other purposes are eliminated; to provide an apparatus wherein the V-abrading material is supplied directly from the grading means to the grinding apparatus, and wherein all of the material supplied at any time is of substantially the same degree of iineness and adapted tol suit the kind of grinding then being done, is supplied in conjunction with the' proper amount of water necessary for each ope 'ation, to the end that a maximum economy in the use of abrasive is attained and the 'time necessary to treat the glass reduced to a minimum, and finally; to provide a compact arrangement of apparatus requiring little .attention 'and wherein the amount ot' labor `is reduced to aminimum. (.)ne elnbodimentof my invention is shown in the accompanying drawings, wherein Figure l is a diagrammatic plan view of the general arrangement of the' assembled apparatus,

Figure Q is a side elevation of the front. portion of the apparatus,

Figure 2a is a side. elevation of the rearv portion of the apparatus, on the scale somewhat enlarged over that of Figure 2,

Figure 3 is a plan view of the apparatus as shown in Figure 2,

Figure L.this a side elevation partly in cross-section of the smallest. grading tank, and

Figure 5 is a sectional view showing a modified means for suspending the tank of Figure 4.

ln my co-pending applications Serial Nos. 384.637. 384.638. and 384.639. all liled'on July 19, 1907. I have .illustrated and de- Specication of Letters Patent.

Patented sept. 2i, ieee.

Serial No. 507,260.

scribed in detail the method and apparatus employed in securing the grading of material and one application of such apparatus to glass grinding operations. rfhe present invention involves a new and different application of the grading apparatus of the general type disclosed in such co-pending applications to use in conjunction with plate glass grinding and smoothing mechanism. Briefly stated the apparatus in its preferred form comprises a plurality of grinding tables, each provided With a pair of grading tanks and a main grading tank for serving all of the pairs of tanks, which grading tank separates thenngraded abrading material into three.

grades, the lirst or coarsest grade going to one of each of ,the pairs of tanks for the facing operation, the second or linest ,grade going to the other-one of each of the pairs of tanks for the finishing operation, and the third or intermediate grade which is too fine for facing' economically and too coarse for finishing or being more valuable ash byproduct going to a tank for use as a byproductin some other art or is thrown away. When' this sand is sufficiently pure it is advantageously used for the batch from which the glass is made. The apparatus also includes means vfor transferring the material from the main tank to the pairs of tanks, means for carrying the drainage from the tables to the main tank for regrading of the mixture in suchmain tank, and means for cont-rolling the v discharge from the pairs of tanks to the grinding mechanism.

Referring first to the general arrangementshown in Figure 1 A are the grinding tables preferably arranged in line as shown, and provided with the usual pair of runners. and all draining into the comlnon trough or canal B, which has a rearward portion C leading to the pit D indicated in dotted lines; Eis the preliminary grading tank. with its lower end communicating with the pit D, Which tank is adapted to separate the sand to be graded into three grades, the coarsest of which is discharged into one of the tanks F to be used subsequently for the facing operation, the finest grades discharging into the trough G for the finishing operation` and the intermediate grade Which is too fine for `facing economically, and too coarse for finishing discharging into the tank H': l and K arepairs of grading tanks in position f to discharge to the grinding tables A,the smallest tanks I` receiving the line sand from the trough Gr for the finishing operation, and the largest tanks K receiving the sand from the sand pile L and tanksF for the facing operation; O is an overhead track adapted to carry a trolley or conveyer, by means of which the sand from the sand pile L and tank F is carried to the'four grading tanks K; M is the-sewer to which the overfiow from the various tanks and 4troughs is conducted by means of the pipes shown, and N is the water main forI supplying water to the grading tanks I, K.

Referring now to Figures 2 and 2a. which show in siole elevation one of the grinding tables and one eachof'the tanks l, K, the tank E and the operating mechanism therefor, it will be seen that the table A which is of any approved type, has supported thereover a distributing trough 1, provided on its under side with perforations for supplying a vmixture of abrasive and water from the grading tanks I and K, and is surrounded by a ditch or gutter 2 for receiving the drainage from the table, and conducting the mixture to the canal B from which point the mixture drains to the canal C Aand thence to the pit D as shown in Figures 1 and 2a. As indicated in Figure 2a, the grading tank E is located over the pit D andis provided with an admission pipe 3 for conducting the mixture of abrasive and water from the pit D to the tank, and this pipe isn provided with a lifting pump 4 preferably of the centrifugal type indicated. The grading tank E is made of conical form in .order to provide for a change of velocity in the water passing up therethrough and thus Secure grading of the material in grades of constantly decreasing coarseness from the bottom of the tank to the top, and has preferably four outlet members 5, 6, 7 and 8 as' shown. The outlet member 5 is adapted to discharge to either one of the two tanks F in which the abrasive is stored for future use, and the overflow from such tank is delivered to the sewer M by means of the pipe 9. This grade includes the coarser particles to be used in the facing` operation, and this material is conveyed as needed to the tank K by means ofthe conveyer 10 carried by the track O. The discharge pipe 6 leads from the tank to the trough G those'portions of the sand suitable for the finishing operation, which trough G branches laterally as shown in Figure 1in order to carry the mixture' over they four tanks I. That portion-of the tank containing those particles of abrasive which are too` hne for facing economically and too coarse for lfinishing isconducted by means of the pipe 7` tothe tank H, and maybe "subsequently used asa by-'product 'or disposed lof infany' manner desired. The surplus water andthose portions of the material -vtoo fine forl use are discharged through the overflow pipe 8`to the sewer M. In order to the pump 4 is not in-operation, a ball valve 14 is provided. The tank E is of the type shown in Figure 3 of my co-pending appli- -prevent any backflo\w from the tank when V cations sei-iai NOS. 884,887, 884,888, 884,689,

and there described, `and secures an vaccurate grading of the materialregardless of its characterbecause of the large proportion of fluid to abrading material, and the slight relative area occupied by ythe'abrading material` at any level, which renders any change in interstitial area and velocity due to the material negligible.

The tanks K one of which is shown in Figure-2 grade the coarser abrading material carried from the sand pile L and tanks F on the conveyer 10 for use in the facing operation, and will now be described. Such tank K has connections with the water-main N by means of the pipe 15 leading into the lower end of the tank and the flow is preferably controlled by the automatic valve 16, which valve 16 has a float 17 carried in the conical vessel 18 shown, and a small pet cock 19 is provided for gradually filling the chamber 18 and thus closing the valve as the operation progresses. Any backflow into the pipe 15 is prevented by means of the ball valve 20. The tank is provided at its bottom with the discharge tube 21 leading to the distribution troughv 1,- which distribution trough is supported as shown, for rocking movement, and such rocking is given by means of a water motor 22. This water motor is connected by means of the rod 23 with the lever 24, which carries the end ofv the trough 1, and such motor is operated by the overflow` from the tank passing down Vthrough the pipe 25. The outflow from the motor 22 passes through the pipe 26 to the trough or gutter 2, and serves to wash' the abrading material therefrom. The main N is connected to the pipe 26 by means of the pipe 27' which is also controlled by the automatic valve 16 in such manner that as the flow of water in trough 1, so that the single trough `serves to carry the, mixturefr om bothfthe'tanks I and K. As before stated, the tanks I are fed fromthe trough'G, and in orderfto ire'- duce -the attention necessary' to theoperation of these tanks automatic means are'provided for cutting out the flow of the liquid l of' abrading material and water carried up from the trough to the tanks, when a predetermined density thereof is secured. To this end each of the tanks is suspendedA as v shown in detail in Figure 4 of the drawing. As here shown, the opposite sides of the tank are provided with bearing blocks28, which bearing blocks cooperate with edges 29 carried by the yoke 30, which yoke is pivoted4 asl shown, upon the bearing blocks 31 mounted on supporting beams 32 at the sides of the tank. The yoke is counterbalanced by meansy of a weight 33 adjustable longi tud-inally of the member 30. A rod carrying the ball valve 34 is secured to the top of the tank in position to engage an opening through the bottom of the trough, and by adjusting the weight 33 along the lmember 30, the tank may be so balanced as to tilt downward closing the valve 34 when a predetermined density of liquid is secured. The material is graded in the. tank by means of the pipe 35 leading from the main, which pipe 35 has a flexible connection 36 wlth the bottom of the tank. Provision is made for the overflow by means of the pipe 37 leading to the drainage pipe 38, which returns the liquid to the sewer M. 1When all the tanks I have been filled and the valves closed, an overow takes place from the trough (l through pipe 39 (Figure `l and back to the drainage pipe 38.

Snflicient sand. to face 'the ronghest set possible is taken from the sand pile L and boxesV F' and placed inthe grading tank K.

rilhe main N is then permitted to send a flow of water through the pipe 15 to theJ bottom of the tank K and the material therein is graded. The grinding mechanism isv then started and the cock in the pipe 21 is opened, together with the pet cock 19. This permits of a discharge of the coarse sand from the tank tothe distributing trough 1, which trough is agitated by the mot-or -22 in order to distribute the sand. over the table. The coarser abrading material at the bottom of the tank K is used. first, and 'the filling of the tank 18 and raising of float 17 gradually close the valve 16, thus reducing the upward velocity in the tank and permitting the iiner grades of material'to settle to a point at which they may be discharged through the pipe 21, and furthermore, preventing the ratio of water to abrading material from becoming too great. The tank 18 is constructed with the diverging wall shown, so that theclosure becomes sloweras the end of the operation is approached, at which time the entire flowv of water to thel tank may be cnt ofi'I and such flow directed through'the pipe 29 to wash out the gutter 2. `When the sand being discharged from the tables A has been washed through the glitters 2, Y), and C, to the pit D, the pump 4 below the tank E is started, and a mixture through the tank and graded, the finer material passing to the space between the dotted lines 1,1 and 12, and thence discharging through the pipe 6 to the trough G, the coarser material filling the space below the dotted line 13 and discharging through the pipe to the tank L, the material unsuitable for grinding lying between theldotted lines 11 and 13, discharging to the tank H, and the overflowabove .the dotted line 12 discharging to the sewer M. The flow of liquid through'the trough G to the tanks I is continued until a predetermined density is attained in these tanks, at which time the tanks will move downward closing their valves 34. The platenow being ready for finishing, the valve at the bottom of the tank I is opened, permitting the finer abi-adingmaterial to feed on to the table. As in the other operation, the coarser material in the tank is applied first, followed by'finer and finer quality as the finishing progresses, until the finishing operationV is concluded. It will be understood that according to the chara'lcter of the material in the tank I, the llow of water through the pipe 36 may be continued through the entire operation, or

it may be stopped at the beginning of the discharge of the material, or it may be shut ofi' prior to the starting of the finishing operation. It will be seenfrom the foregoing that throughout the operation, the size of the particles of abrading material employed decreases as the glass is reduced, so that at every stage of the procedure a size of abrading material best suited for the work to be done is employed. By employing a. sufficiently line grade of sand in the tank I, a suiiicient high finish may be obtained to avoid the additional finishing opera-tion Withemery heretofore considered necessary.

'In Figure 5 a modified arrangement for supporting the tank I and' controlling the How of liquid is shown. As here illustrated, thetank I is provided with a yoke 40 provided with a bearing edge 41, which bearing edge 41 engages the end of the balancing lever 42 which is in turn supported by means of the supporting frame 43 carried by the longitudinal beams 44 arranged above the trough G. The valve 45 is carried by a rod 46 guided in the frame 43, and its lower end is adapted to fit into the pipe 49, which `pipe 49 is carried in the bot-tom of the trough G and depends-into the tank. The valve is closed when the tank descends, by the engagement of the upper end of the rod 46 by the end of the lever 42. In order that the valve 45 may be operated by hand when de- `sired, a lever 47 is secured thereto, which lever is pivoted on the supporting frame 43 and has at its outer end an operating cord 48.

-The operation isvas follows: The operator having pulled the cord 48, opens the valvev of the plug. 45 prevents any material from lentering thetank I until the operator pulls the cord 49.

This arrangement prevents an inflow from the trough G when the tank has been only partially emptied. y

Having thus described my invention and illustrated its use, what I claim as new and desire to secure by Letters Patent is the following 1. Apparatus for supplying abrasive to grinding and smoothing mechanism, comprising in combination with a mechanism using an abrasive withI water, and having a drainage pit, a preliminary grading tank having an admission passage leading from the pit to the bottom. of the tank, means for securing a continuous flow of liquid up 1 through such passage and the tank, discharge passages at different levels in the tank of small capacity as compared with the capacity of the admission passage, receptacles for receiving the flow from the said discharge passages, and means for supplying the abrading material to the said mechanism. i

2. Apparatus Jfor 'supplying' abrasive to grinding and smoothing mechanism, comprising in combination with a 'mechanism using an abrasive with water, and having a drainage pit, a preliminary grading tank having an admission passage leading from the pit to the bottomof the tank, means for securing a flow of liquid up through such passage and the tank, a second grading tank in position to discharge to the said mechanism and a passage for conducting a portion of te liquid fromthe first tank to the second tan 3. Apparatus or supplying abrasive to grinding and smoothing mechanism, comprising in combination with a` mechanism using an abrasive with water, and having a drainage pit, a preliminary grading tank having an admission passage leading from the pit to the bottom of the tank, means for securing a'low of liquid up through such passage and the tank, a second grading tank in position to discharge to the said mechanism, means for securing an upward flow of liquid. therethrough, and a passage for conducting a portion of the liquid from the rst tank to the second tank. y i

4. Apparaus for supplying abrasive to. grinding and smoothing mechanism, com` prising in combination with a mechanism using an abrasive with water, and having a having an admission passage leading from the pityto the bottom of the tank, means 'for securing a flow of liquid up through-such passage and the tank, a second grading' tank in position to discharge to the said mechanism, and a passage for conducting a portion of the liquid from the first tank to the second tank, a receiving tank and a discharge passage thereto from the lower portion of the preliminary grading tank for receiving the coarser material from the preliminary grading tank.

5. Apparatus for supplying abrasive to grinding and smoothing mechanism, comprising in combination with a mechanism using an abrasive and Water and having a drainage pit, a Agrading tank in position to discharge to said mechanism, a passage for introducing a liquid containing divided material in suspension thereto, and .means controlled by the wei ht of the mixture in the tank for cutting o "the flow thereto, when a predetermined density of the mixture in the tank is secured. l

6. Apparatus for supplying abrasive to grinding and smoothing mechanism, com-y prising in combinationy with a mechanism using an abrasive and water and having a drainage pit, a grading tank in position to discharge to said mechanism, means for securing a llow of liquid upward from the bottom thereof, a passage for introducing a liquid containing divided material in suspension thereto, and means controlled by the weight of the mixture in the tank for cutting off the l'low thereto, when a predetermined density of the mixture in the tank is secured. 7 Apparatus for supplying abrasive to grinding and smoothing mechanism, com-` prising in combination with a mechanism using an abrasive and water and having a drainage pit, a grading tank having an admission passage ,at its bottom, means'for securing a flow of liquid containing in suspension divided material to be4 graded up through the passage and tank, a second tank in position to discharge to the said mechanism, a vpassage leading from the lirst grading tank to the second grading tank, and meansv for automatically 'cutting off the flow to such secondi-tank when a predetermined denl sity of the mixture therein is secured.

8. Apparatus for supplying abrasive to grinding and smoothing mechanism, .com-

prising in combination with a mechanism yusmg an ^sion divided material to be graded` up.

e and tank, a second tank through the passa arge to the said mechanin position to disc ism, a passage leading from the first grading drainage pit, a preliminary grading tank tank to the second grading tank, and means through the passage and tank, a second tank in position to discharge to the said mechanism, a passage leading from the first grading tank to the second grading tank, means for securing a flow of liquid upward from the bottom thereof, and means controlled by the weight of the mixture in the second grading tank for cutting ofi the flow to such second grading tank when a predetermined density of the mixture is secured.

l0. Apparatus for supplying abrasive to grinding and smoothing mechanism, comprising in combination with a mechanism using an abrasive with water, and having a movable distributing trough thereover, a grading tank in position to discharge to the trough and provided with means for securing an upward flow of liquid from the bottom thereof, a water motor for moving the distributing trough and an overflow passage from the grading tank whereby the motor is operated.

11. Apparatus for supplying abrasive to grinding and smoothing mechanism, coinprising in combination with a mechanism using an abrasive with water and having a movable distributing trough thereover, a grading tank in position to discharge to the distributing trough and having an admission pipe for securing an upward iiow of fluid from the bottomvthereof, a pipe secured to the admission pipe and leading to the drainage trough and a valve automatically operated for gradually cutting od the supply of water to the tank as the operation progresses and simultaneously adinittiing water to the pipe leading to the drainage trough.

l2. Apparatus for supplying abrasive to grinding and smoothing mechanism, comprising in combination with a mechanism ua pair ot grading tanks in position to discharge to the said mechanism, one of which is provided with means for securing an upward How of liquid, a preliminary grading tank adapted to separate the abrading material into a coarse grade for facing and a line grade for finishing, means for conveying the coarse material to the one of the said air of grading tanks having the upward gow of water and means for conveying the fine material tothe other of the said pair of grading tanks.

. 13. Apparatus for supplying abrasive to grinding and smoothing mechanism, comprising in combination with a mechanism a pair of grading tanks in position to discharge to the said mechanism one of which is provided with means for securing an upward tioW of liquid, a preliminary grading tank adapted to separate the abi'adingmaterial into a coarse grade for facing and a tine grade for finishing, means for conveying the coarse material to the one of the said' pair of grading. tanks having the upwardV iiow of Water and means for conveying the iine materiall tothe other of said pair of grading tanks.

14. Apparatus for supplying abrasive to grinding and smoothing mechanism, comprising in combination with a plurality of mechanisms using an abrasive with water, a pair ot' grading tanks in position to 'discharge to each mechanism one of which is provided with means for securing an upward iow of liquid, a preliminary grading tank adapted to separate the abrading material into a coarse grade for facing and a tine gradefor finishing, means 'for conveying the coarse materialfto the one of each of the said pairs of grading tanks having the upward tlow of water and means for conveying the line material to the other of each ot' the said pairs of grading tanks.

15. Apparatus for supplying 'abrasive to grinding and smoothing mechanism, coniprising in combination 'with a plurality of -mechanisms using an abrasive with water 100 and having receiving troughs leading to a common pit, a pair of grading tanks for each niechanisni.in position .to discharge thereon, one of which is providedwith means t'orA securing an upward4 flow of liquid, a 105 preliminary grading tankconiiected at its bottom with the said pit and having means for giving a flow of water therefrom up through the tank, and means for conveying the abrasive from one level the preliminary grading tank to the one each of the pairs of tanks having the upward flow of water and for conveying the abrasive from a ditferent level of the preliminary grading tank to the other of said pairs of tanks.

16. Apparatus for supplying abrasive to grinding and smoothing mechanism, comprising in combination with a plurality of mechanisms using an abrasive with water and having receiving troughs leading to a common pit, a pair of grading tanks for each mechanism..` in position to discharge thereon and each having means for securing an upward iow of liquid, a preliminary grading tank-connected at its bottom with 125 thesaid pit and having means for giving a flow of water therefrom up through the tank, and means for conveying the abrasive from one level of the preliminary grading tank to one each of the pairs of tanks and l conveying the abrasives to the pairs of tanks.

mechanism in position to discharge thereon for conveying the abrasive from a different level of the preliminary grading tank to the other of said pairs of tanks.

17. Apparatus forsupplying abrasive to 4grinding and smoothing mechanism, comprising in combination with a plurality of mechanisms using an abrasive with water and having receiving troughs leading to a common pit, a pair of grading tanks-for each one of which is provided with means for securing an upward flow of liquid, a preliminary -grading tank connected at its bottoml with the said pit and having means for giving a continuous flow of liquid therefrom up through the tank, passages at different levels ofthe preliminary rading tank for conductingtwo grades of't e abrasives continuously therefrom,` the combined capacity of such passages being small as compared with the flow of liquid from thepit, and means for 18. Apparatus for vsupplying abrasive to grinding and smoothingmechanism, com- I prising in combination with a plurality of i mechanisms using an abrasive with water and having receivin troughs leading to a common pit, a pair o grading tanks for each mechanism in position to discharge thereon one of which is provided with means for securing an upward flow of liquid, a prelim# inary grading tank with one each of thev pairs of tanks, means for conducting the coarser abrasive from the bottom of the said preliminary grading tank to a receptacle i and means for conveying such abrasive to the other of said pairs of tanks which are provided .with the upward flow of liquid.

In testimony whereof I have hereunto signed my name in the presence of the two subscribed witnesses.

' HALBERT K. HITCHCOCK. Witnesses:

F. E. GArrHER, ARCHWORTH MARTIN; 

